THE blood-letting triggered by the Tory leadership contest intensified yesterday as former chancellor Lord Lamont became the latest of the party's "grandees" to join the increasingly bitter fray.

Lord Lamont criticised former premier John Major - the man who appointed and then sacked him as chancellor - over his outspoken attack earlier this week on his predecessor, Baroness Thatcher.

He said Mr Major's claim that she had caused immense damage to his government by encouraging young Euro-sceptics such as leadership contender Iain Duncan Smith to rebel against him, had been "regrettable" and "a mistake".

Meanwhile, former deputy prime minister Lord Heseltine turned on William Hague, describing his "Euro-phobic" general election campaign as a "disaster" for the party.

Lord Heseltine, who, like Mr Major, is backing Kenneth Clarke for the leadership, warned that if Mr Duncan Smith won the Tories could be consigned to opposition for the next 15 years.

The acrimonious clashes between the party's "big guns" of the 1980s and 1990s threatened to drown out the main battle between Mr Clarke and Mr Duncan Smith, which was once again dominated by exchanges over Europe.

In an interview with BBC Radio 4's Today programme - 24 hours after Mr Major appeared on the same programme - Lord Lamont said that his former boss had been wrong to blame Lady Thatcher for his govern-ment's difficulties.

"John Major's difficulties as prime minister were not caused by Mrs Thatcher, they were inherent in the situation," he said.

"I don't think he did himself any good by resurrecting this.

"I mean Mrs Thatcher had her problems with Ted Heath. It always happens."

Meanwhile Lord Heseltine, in an article for the Evening Standard in London, attacked Mr Hague for abandoning the "pragmatic" approach to Europe adopted by every Conservative prime minister since Harold Macmillan.

"It was replaced by a brand of Euro-scepticism, indeed Euro-phobia, unknown in this country since I first stood as a Conservative candidate in 1959," he said.

"The result was a disaster - 2001 produced the worst Tory result in living memory."

And he warned that if Mr Duncan Smith became leader, the outcome of the next general election could be just as bad for the Tories.

"A Duncan Smith victory will tell the British people that the Conservative Party is now only interested in talking to itself.